diff mbox series

[v7,06/11] arm64: dts: mediatek: set vmc regulator as always on

Message ID 20230203-evk-board-support-v7-6-98cbdfac656e@baylibre.com (mailing list archive)
State Handled Elsewhere
Headers show
Series Improve the MT8365 SoC and EVK board support | expand

Commit Message

Alexandre Mergnat May 11, 2023, 4:29 p.m. UTC
From: Fabien Parent <fparent@baylibre.com>

On downstream, we observe that the MSDC IP (used by the emmc, the micro
SD card and the WiFi) isn't working properly if the VMC regulator is
shutdown.

Make sure it is always on.

Signed-off-by: Fabien Parent <fparent@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com>
---
 arch/arm64/boot/dts/mediatek/mt8365-evk.dts | 5 +++++
 1 file changed, 5 insertions(+)

Comments

AngeloGioacchino Del Regno May 15, 2023, 11:44 a.m. UTC | #1
Il 11/05/23 18:29, amergnat@baylibre.com ha scritto:
> From: Fabien Parent <fparent@baylibre.com>
> 
> On downstream, we observe that the MSDC IP (used by the emmc, the micro
> SD card and the WiFi) isn't working properly if the VMC regulator is
> shutdown.
> 
> Make sure it is always on.

I don't understand the power tree of this board: if your VQMMC is VIO18 and
*not* VMC, why is that required?

The real question is if we're facing one more supply as requirement for newer
MediaTek SoCs and whether it would be a better idea to add that to the actual
driver (and/or as a power domain supply!!!) to both better represent the power
tree and to eventually allow deep power saving states.

Regards,
Angelo

> 
> Signed-off-by: Fabien Parent <fparent@baylibre.com>
> Tested-by: Kevin Hilman <khilman@baylibre.com>
> Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com>
> ---
>   arch/arm64/boot/dts/mediatek/mt8365-evk.dts | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/mediatek/mt8365-evk.dts b/arch/arm64/boot/dts/mediatek/mt8365-evk.dts
> index 752007d0598e..5d69b39c8746 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8365-evk.dts
> +++ b/arch/arm64/boot/dts/mediatek/mt8365-evk.dts
> @@ -137,6 +137,11 @@ &mt6357_pmic {
>   	#interrupt-cells = <2>;
>   };
>   
> +/* Needed by MSDC IP */
> +&mt6357_vmc_reg {
> +	regulator-always-on;
> +};
> +
>   &pio {
>   	gpio_keys: gpio-keys-pins {
>   		pins {
>
Alexandre Mergnat May 22, 2023, 2:24 p.m. UTC | #2
Hi Angelo

Le lun. 15 mai 2023 à 13:44, AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com> a écrit :
>
> Il 11/05/23 18:29, amergnat@baylibre.com ha scritto:
> > From: Fabien Parent <fparent@baylibre.com>
> >
> > On downstream, we observe that the MSDC IP (used by the emmc, the micro
> > SD card and the WiFi) isn't working properly if the VMC regulator is
> > shutdown.
> >
> > Make sure it is always on.
>
> I don't understand the power tree of this board: if your VQMMC is VIO18 and
> *not* VMC, why is that required?

I don't have the full history of the downstream, but I think there is
a schematic
issue or HW conception issue because I see an extra pin "MSDC1_INSI" (which
isn't part of MSDC IP) with VIO18 pull-up. That's why, I guess, VQMMC = VIO18
for MMC1. But since DVDD28_MSDC1 = VMC, VQMMC should be equal
to VMC.

The always-on will be removed.

Regards,
Alexandre
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/mediatek/mt8365-evk.dts b/arch/arm64/boot/dts/mediatek/mt8365-evk.dts
index 752007d0598e..5d69b39c8746 100644
--- a/arch/arm64/boot/dts/mediatek/mt8365-evk.dts
+++ b/arch/arm64/boot/dts/mediatek/mt8365-evk.dts
@@ -137,6 +137,11 @@  &mt6357_pmic {
 	#interrupt-cells = <2>;
 };
 
+/* Needed by MSDC IP */
+&mt6357_vmc_reg {
+	regulator-always-on;
+};
+
 &pio {
 	gpio_keys: gpio-keys-pins {
 		pins {